1. Field of Invention
The present invention relates to a PCV valve. More particularly, the present invention relates to a PCV valve which may not block flowing of blow-by gas and may prevent noise and abrasion.
2. Description of Related Art
A general blow-by system allows combustion blow-by gases to escape from the engine crankcase without getting released into the environment and to return to an intake manifold through a head cover and the blow-by system includes a PCV (Positive Crankcase Ventilation) valve which controls flowing of blow-by gases.
FIG. 7 is a cross-sectional view of a general PCV valve.
Referring to FIG. 7, a general PCV valve includes a cover 110 of which an inlet 112 is formed thereto and a body 120 of which an outlet 122 is formed thereto and the body 120 is connected to the cover 110 and an orifice 160 which is disposed therein.
A valve body 130 is elastically supported by a valve spring 140 and the valve spring 140 is compressed according to pressure differences between the outlet 122 connected to an intake manifold (not shown) and the inlet 112 connected to a head cover (not shown) and then blow-by gas flows into the intake manifold.
However, if pressure differences between the outlet 122 and the inlet 112 are increased, the valve spring 140 may be completely compressed so as to block flowing of the blow-by gas or the valve body 130 may block a hole formed to the orifice 160 or the outlet 122.
To solve those problems, as shown in FIG. 7, a spring 150 is provided near the outlet 122 or a stopper (not shown) is provided.
However, the general PCV valve further includes a cushion spring and elements for configuring the cushion spring and thus element numbers are increased and also production cost is increased.
And also, if a stopper and so on is configured, element numbers are increased and noise and abrasion induced by impacts of the stopper may be occurred.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.
The information disclosed in this Background section is only for enhancement of understanding of the general background of the invention and should not be taken as an acknowledgement or any form of suggestion that this information forms the prior art already known to a person skilled in the art.